The present invention relates to aircraft, inflight, refueling devices commonly known as drogues. More specifically, but without limitation, the present invention relates to an air refueling drogue that is attached to a fuel hose and deployed rearwardly from the storage pod of a tanker aircraft to provide a bell shaped, stable target for a receiving aircraft in need of fuel.
When flying long range missions over water or mountainous terrain, it is often desirable and preferable to refuel an aircraft in flight. This can be a dangerous and sometimes difficult task. If a mishap occurs, the receiving aircraft will usually be lost. Such an operation requires a tanker aircraft and a means for transferring fuel from the tanker aircraft to the receiving aircraft.
One widely used method for conducting such an operation includes the inflight deployment of a drogue and fuel transfer hose from a tanker aircraft and into the airstream. The fuel transfer hose is fluidly attached, on one end, to a fuel source in the tanker aircraft and, on the other end, to a valve means in the drogue. During deployment from the storage pod, aerodynamic (drag) forces act on the drogue pulling the drogue and fuel hose rearwardly until fully deployed (usually about 50 feet). The drogue "flies" in a stable manner during and after deployment thereby preventing damage to the tanker aircraft and presenting a predictable, stable target for the pilot of the receiving aircraft. A probe in the receiving aircraft is then brought into alignment with the drogue and forcibly inserted and locked into a coupling device located at the center of the drogue. Fuel is then transferred from the tanker aircraft to the receiving aircraft.
Although existing drogues have worked effectively for many years, there are many inadequacies in these present designs. Existing drogues are complex, employing over 780 metal parts. A single failure can be disastrous and become "foreign object damage" (FOD) if ingested by the receiving aircraft jet engine. In addition, existing drogues are costly to build, repair and maintain. Sometimes, the probe on the receiving aircraft can become bound up or even pierce the fabric cover on existing drogues damaging the drogue assembly and preventing the refueling operation. In addition, the drogue must be small enough to be easily stored in the storage pod of the tanker aircraft yet be large enough when deployed to allow the pilot of the receiving to insert and lock the refueling probe. It is therefore desirable that a drogue have a minimum number of parts to reduce FOD potential. It is also desirable that a drogue be of a design that results in a minimal cost to build, repair and maintain. At the same time, it is desirable that a drogue be collapsible for the purpose of storage and expandable for the purpose of presenting a large target. It is also desirable that the drogue be durable to withstand repeated altercations with the probe of the receiving aircraft.
Accordingly, it is the object of the present invention to provide a drogue that will have minimum FOD potential. It is a further object of the present invention to provide a drogue that will be inexpensive to build, repair and maintain. It is another object of the present invention to provide a drogue that will fly in a predictable stable manner. It is still another object of the present invention to provide a drogue that will easily open up when ejected into the airstream and easily collapse when withdrawn back into the storage pod. It is also an object of the present invention to provide a durable drogue that can withstand repeated altercations with a refueling probe.